如何在方向更改时保持适配器中动态创建的视图的已检查项目

Question

我正在做什么 ::我有一个horizontal listview，如下所示我正在动态填充项目

正在发生的事情 ::由于动态创建的listview onorientation更改了已选中项目未选中

问题：如何从适配器收集已检查的项目并重新检查orientation change上选定的内容

---

AdpBufTypeSearch.java

public class AdpBufTypeSearch extends BaseAdapter{

    private HashMap<String, String> objHashBufType;
    SparseBooleanArray mBufTypeArr = new SparseBooleanArray();
    private ArrayList<HashMap<String, String>> objListBufType;
    Context mContext;

    public AdpBufTypeSearch(Context _mContext,ArrayList<HashMap<String, String>> _objListBufType) {
        mContext=_mContext;
        objListBufType=_objListBufType;
    }

    @Override
    public int getCount() {
        return objListBufType.size();
    }

    @Override
    public Object getItem(int position) {
        return null;
    }

    @Override
    public long getItemId(int position) {
        return 0;
    }

    //LOGIC:: result will be a set on which ones are selected Ex:: 0,1,2,4
    public String getSelectedBuffetType() {
        //This final value(strBufTypeId) is returned when we access from class
        String strBufTypeId="";

        for(int i=0;i<objListBufType.size();i++) {
            HashMap<String, String> objHashBufType = objListBufType.get(i);
            if(objHashBufType.get("selected")=="1") {
                strBufTypeId=strBufTypeId+objHashBufType.get(buf_type_mas.COLUMN_BUF_TYPE_ID);
                strBufTypeId=strBufTypeId+",";
            }
        }
        //remove the last "," in the string
        if(strBufTypeId.lastIndexOf(",")>0) 
            strBufTypeId=strBufTypeId.substring(0, strBufTypeId.lastIndexOf(","));
        return strBufTypeId;
    }


    /*LOGIC:: <HashMapObject(objHashBufType)> ==> their value of key(selected) is updated to "1" else key(selected) is updated to 0 */
    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

        View retval = LayoutInflater.from(parent.getContext()).inflate(R.layout.adp_meal_type, null);

        final TextView buf_type_name = (TextView) retval.findViewById(R.id.buf_type_name);
        TextView buf_type_id=(TextView) retval.findViewById(R.id.buf_type_id);
        ImageView buf_type_image=(ImageView) retval.findViewById(R.id.buf_type_image);
        final LinearLayout imgBkgSelector=(LinearLayout) retval.findViewById(R.id.imgBkgSelector);

        imgBkgSelector.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {

                //LOGIC:: If Selected unselect it and if it is unselected select it
                if(mBufTypeArr.get((Integer) imgBkgSelector.getTag())==true){
                    //INNER-LOGIC:: Background not selected
                    mBufTypeArr.put((Integer) imgBkgSelector.getTag(), false);
                    objHashBufType = objListBufType.get((Integer) imgBkgSelector.getTag());
                    objHashBufType.put("selected", "0");
                    imgBkgSelector.setBackgroundColor(Color.parseColor(mContext.getString(R.color.cBlack)));
                    buf_type_name.setTextColor(Color.parseColor(mContext.getString(R.color.cWhite)));
                }
                else{
                    //INNER-LOGIC:: Background selected
                    mBufTypeArr.put((Integer) imgBkgSelector.getTag(), true);   
                    objHashBufType = objListBufType.get((Integer) imgBkgSelector.getTag());
                    objHashBufType.put("selected", "1");
                    imgBkgSelector.setBackgroundColor(Color.parseColor(mContext.getString(R.color.cBlue)));
                    buf_type_name.setTextColor(Color.parseColor(mContext.getString(R.color.cWhite)));
                }
            }
        });

        imgBkgSelector.setTag(position);

        //Essential code for retain the Background check part on scroll of images
        if(mBufTypeArr.get(position)==true){

            imgBkgSelector.setBackgroundColor(Color.parseColor(mContext.getString(R.color.cBlue)));
            buf_type_name.setTextColor(Color.parseColor(mContext.getString(R.color.cWhite)));   

        }else{

            imgBkgSelector.setBackgroundColor(Color.parseColor(mContext.getString(R.color.cBlack)));
            buf_type_name.setTextColor(Color.parseColor(mContext.getString(R.color.cWhite)));

        }
        // Get the position
        objHashBufType = objListBufType.get(position);

        // Capture position and set results to the TextViews
        //Capitilize the names
        String capitalizedBufTypeName = WordUtils.capitalizeFully(objHashBufType.get(buf_type_mas.COLUMN_BUF_TYPE_NAME), ' ');
        buf_type_name.setText(capitalizedBufTypeName);
        buf_type_id.setText(objHashBufType.get(buf_type_mas.COLUMN_BUF_TYPE_ID));

        Picasso.with(mContext)
        .load(mContext.getString(R.string.URL_BUFFET_TYPE_IMAGE).trim()+objHashBufType.get(buf_type_mas.COLUMN_BUF_TYPE_IMAGE).trim()).resizeDimen(R.dimen.filter_image_width,R.dimen.filter_image_height).centerCrop().into(buf_type_image);

        return retval;
    }

}

FrgMdSearch .java

public class FrgMdSearch extends Fragment {
    private HashMap<String, String> objHashBufType;
    private ArrayList<HashMap<String, String>> objListBufType=null;
    private AdpBufTypeSearch bufTypeAdapter;

    @Override
    public void onActivityCreated(Bundle savedInstanceState) {

        super.onActivityCreated(savedInstanceState);
        //Setting the adapter for buf images<---DYNAMIC VIEWS--->
        setAdapterBufImages();
    }
    private void setAdapterBufImages() {
        bufTypeAdapter=new AdpBufTypeSearch(getActivity(),objListBufType);
        hListView.setAdapter(bufTypeAdapter);       
    }
}

Answer 1

在onSaveInstanceState方法中发生方向更改时，您需要保存已检查项目的位置还要在AdpBufTypeSearch适配器中创建一个getter方法，该方法返回已检查项目的当前位置和setter方法设置选中的项目。

<强>样品：

@Override
public void onSaveInstanceState(Bundle outState) {
    super.onSaveInstanceState(outState);

    outState.putInt("position", bufTypeAdapter.getCheckedPosition()); //getCheckedPosition must return the checked item position

}

在片段的oncreateView中

@Override
public void onActivityCreated(Bundle savedInstanceState) {

    super.onActivityCreated(savedInstanceState);
    //Setting the adapter for buf images<---DYNAMIC VIEWS--->
    setAdapterBufImages(savedInstanceState);

}

private void setAdapterBufImages(Bundle savedInstanceState) {
    bufTypeAdapter=new AdpBufTypeSearch(getActivity(),objListBufType);
    if(savedInstanceState != null)
    {
       bufTypeAdapter.setCheckedItem(savedInstanceState.getInt("position")); //will set the checked item
    }   
    hListView.setAdapter(bufTypeAdapter);       
}